Within our intestine live a vast community of bacteria (trillions of them in fact), collectively known as the gut microbiome.
The gut microbiome is of interest in nutrition because research has revealed it plays an important regulatory role within the body. What is so exciting about the microbiome is that, through healthy food choices, we can manipulate the population levels of the community of microbes living within.
By doing so, we can enjoy better mood, better immunity, faster metabolism and improved brain functions.
The key to a healthy and beneficial gut microbiome is bacterial diversity; with studies revealing the more varied the bacteria, the better the individual’s health. Equally, it was found that in cases of asthma, obesity and allergies, as well as in those people who lived with unexplained fatigue and lethargy, there was a less diverse gut microbiome. So how do we increase the diversity of our gut microbiome? We eat more fiber, fresh vegetables and fruits! The “good” bacteria in our gut feed on plant fiber, therefore increasing the amount of vegetables, fruit and whole grains in our diet will help to boost these bacterial populations. The microbiome suffers when the diet is low in fiber, high in sugar, artificial sweeteners, and high in saturated fat.
Why is it so important to keep the gut microbiome divers?
Our modern-day living may provide a perfect storm for dysbiosis (i.e., low level of diversity which is predominated by “bad” bacteria) of the gut. We lead stressful lives with fewer social interactions and less time spent with nature, our diets are typically deficient in fiber, we inhabit oversanitized environments and are dependent on antibiotic treatments. All these factors can influence the gut microbiome and so may be affecting our behavior, and physical and psychological well-being.
The bottom line is, the more “good” bacteria cooperate with each other in your gut, the more positive physiological functions can take place in your body. Thus the more resilient you become against environmental stress, toxins, and diseases.
Just to mention a few physiological functions in which our gut microbiome plays vital role:
- Energy levels
- Enzyme production
- Immune system function
- Inflammation management
- Mental clarity
- Metabolism and healthy weight
- Neurotransmitter synthesis
- Nutrient absorption
- Response to stress
- Vitamin synthesis
How is this all possible?
We now know that the gut microbiome communicates with the brain.
But how does our gut communicate with our brain?
We are only at the beginning of trying to figure this out. Essentially, a conversation is going on all the time between the brain and the gut through the central nervous system. One of the key pathways involves the vagus nerve. Vagus comes from the latin word for ‘wandering’, so this ‘wandering’ nerve sends signals from the brain to all of our organs, and from our organs all the way back to the brain. It is the key circuit recruited during mindfulness training.
And this is just one pathway. There are many other ways in which your gut sends signals to the brain to modify our behavior. And if the conversation between the brain and gut is in any way impaired, there can be outcomes of a variety of neurodegenerative diseases and auto-immune diseases.
Without this connection and without a healthy gut microbiome we are also prone to develop diseases, anxiety, and depression. The microbiome is also the major contributor to the body’s serotonin levels. If you can keep the microbiome fit and healthy, the serotonin it produces can contribute to a better mood and may reduce the occurrence and severity of stress and anxiety.
As you might imagine, nutritionists seek to encourage the growth of the good bacteria in the gut, understanding it can have a positive influence across numerous health issues, as well as being an important factor in digestion and overall balance of the body.
What can we do to keep the gut microbiome healthy?
The bacteria in your gut work hard for you during digestion and, if we can keep the microbiome diverse and healthy, the health benefits are far-reaching across the body. If a nutritionist suspects the microbiome is out of balance (for example if the diet is lacking in foods which support bacterial variety, or if there is a history of high antibiotic use), they may recommend specific foods and supplements. For example, fermented foods could be added to the diet to help encourage a healthy microbiome. Excellent fermented foods for the gut include:
Prebiotics may also be recommended. Prebiotics are a type of plant fiber which our digestive enzymes cannot break down – but the bacteria in our microbiome can, and they love them! A prebiotic-rich diet helps support the growth of beneficial bacterial populations in the gut — typically by fermenting the prebiotic plant fibers and converting it to a useful anti-inflammatory compound called butyrate. Sources of prebiotic plant fibers include:
- Bananas (when unripe)
- Brown rice
- Cashew nuts
- Green peas
- Inulin containing plants (artichokes, asparagus, bananas, chicory, leeks, garlic and onions)
- Wholegrain pasta and rice
Probiotics are a well-known and now popular remedy for gut issues.
When correctly chosen and used, they help by supporting a healthy gut microbiome by introducing the most useful strains down into the digestive tract, which then feed or support beneficial bacterial strains. You can opt either for probiotic supplements or by eating live yoghurt or some other dairy products to which probiotics have been added.
It is definitely worth trying to improve the diversity of our gut microbiome. This is an exciting area of research because unlike your DNA, there is potential for our microbiome to be modified, to allow us to take control of our health and physical wellbeing. So let’s take control and do about it.
Dr. Suzanna Braeger
Holistic Health Coach and Nutritionist
Lecturer (B’n’S Holistic Health Coach, Nutritionist and Wellness Consultant, Yoga Teacher)